Process of making glue by dialysis



NITED STATES more...

ATENT GEORGE LANZENDOERFER, OF BOSTON, MASSACHUSETTS.

SPECIFICATION forming part of Letters Patent No. 392,274, dated November 6, 1888.

Application filed December 19, 1887. Serial No. 258,313.

To aZZ whom, it may concern.-

Be it known that I, GEORGE LANZENDOER- FER, a subject of the Emperor of Germany, residing at Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Processes for the Manufacture of Glue; and I do hereby declare that the followingis a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same.

My invention 'relates to an improved process for the manufacture of glue, and is particularly applicable to liquid glues obtained from the skins and bones of salted fish, though it may be applied to the manufacture of glues from other kinds of raw material in which soluble impurities are likely to be found.

The process of manufacturing glue as at present conducted consists in the extraction of the glue from the raw material by boiling or steaming, and the preservation of the glue so extracted either by dryinginto hard cakes or by treating it with antiseptics. All raw material used by glue-makers contains more or less impurities-particularly salt, lime, and other substances-which would be injurious to the glue if allowed to remain. One of the first things to be done in the manufacture of glue is to cleanse the raw material by carefully Washing it in water, either pure or with acids or alkalies, as may be required. After the stock has been so cleansed the glue is extracted by boiling, and the resulting product either dried into cakes or preserved in liquid form by the use of suitable antiseptics. It is found, however, after the stock has been washed, as above described, that it is likely to become tainted before it is boiled, especially in warm weather, and when the product is a comparatively thin liquor, requiring considerable time for evaporation, or when it is necessary to allow the liquor to stand some time to settle before it is finally evaporated, there is great danger that it will sour and spoil before the operation is completed. If the salt in the material could remain in it until after it was boiled, the danger of the injury above mentioned would be very slight; but the removal of the salts and otherimpurities from the material after it is boiled would be likely, as the art has been heretofore practiced, to injure (No specimens.)

the glue, which is soluble, as are the salts which are to be removed. It therefore has been necessary, as the art has heretofore been practiced, to remove the salts and other impurities from the material before it is boiled and before the glue has been formed.

I have discovered that the salts and other impurities may be removed from the glue after the boiling process more completely than by the old way by the use of a process consisting, essentially, in placing the glue containing the salts and otherimpurities in proximity to water and separated from it by aseptum of parchment paper or equivalent substance. The salts and impurities pass through this septum and are removed by the water on the other side of it. From this discovery it follows that the raw material may be boiled and reduced to glue without first extracting the salts and other impurities, and that the raw material and the glue are thus prevented from decomposition or becoming injured, as above stated. My process therefore consists, first, in boiling the raw material before the salts are extracted, and, second, in subjecting the product of the boiling to the process already explained. I have not shown any particular form of device for accomplishing this, since any convenient method would answer the purpose, aud the process is known in various arts, especially that of beet-sugar making.

It may sometimes be found desirable to extract a portion of the salts by the old method, leaving a portion of them to be extracted after the boiling in the way above explained.

In some instances, particularly when glue is made from fish, there are, besides the salts and impurities, which may be removed by the process already explained, substances which cannot be so removed, consisting of bones and other solid substances. These are to be removed after the boiling by passing the whole mass through a filter-press and leaching out the soluble parts-that is, the glue containing the salts and impurities-from the insoluble parts, (that is, the bones and other solid substances.) This leaching process is one well known in many arts, and therefore does not need any special description.

What I claim, and desire to secure by Let ters Patent, is

1. In the manufacture of glue, the process,

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of extracting the glue from the raw material, ing the soluble from the insoluble parts by together with salts and other impurities eonpassing the whole through a filter-press and 15 tained therein, by subjecting the same to the leaching out the soluble parts, and afterward action of heat and water and afterward reinov- I removing the salts and other impurities from 5 ing the salts and other impurities from the the solution by subjecting it to the action of liquid solution so obtained by subjecting it to 1 water through the medium of parchment'pathe action of water through the medium of per or any equivalent substance, substan- 2o parehmentpaper or any equivalent substance, tially as described. substantially as above described.

1 if )0 F 1. IO 2. lheprocess ofnianufiicturingglucbysubi (LOB jeeting the raw material to the action of heat 1 Witnesses: I and water before the salts and other impurij \ViLLL-m (I. A'rlcixsox,

ties have been extracted therefrom, separat- (nus. ll. Dnnw. 

